Essays about: "lattice"

Showing result 21 - 25 of 280 essays containing the word lattice.

  1. 21. Monte Carlo study of disorder in electronic tight-binding models

    University essay from Lunds universitet/Fysiska institutionen; Lunds universitet/Matematisk fysik

    Author : Carl Pettersson; [2023]
    Keywords : Monte Carlo; Tight-binding model; Falicov-Kimball model; Physics and Astronomy;

    Abstract : Oftentimes solids are described by uniform, periodic lattices. In reality, however, there is often some disorder on some of the sites in the lattice. This disorder may come from, for example, there being a different type of atom or tightly bound electrons resulting in a larger on-site potential, affecting the electronic properties of the lattice. READ MORE

  3. 22. CHARACTERIZATION AND EVALUATION OF A NIPAM POLYMER GEL MRI DOSIMETER SYSTEM

    University essay from

    Author : Christian Waldenberg; [2022-11-08]
    Keywords : Medical physics; Normoxic polymer gel dosimeter; NiPAM;

    Abstract : Purpose: The normoxic polymer gel dosimeter based on N-isopropyl acrylamide (NiPAM) is a promising full 3D-dosimeter with high spatial resolution and near tissue equivalency. However, limited work have been done in vestigating this dosimeter. The dose response and reproducibility of a NiPAM dosimeter was investigated. READ MORE

  4. 23. Determination of Proton Beam Waist Positions Using Beam Position Monitors

    University essay from Lunds universitet/Fysiska institutionen; Lunds universitet/European Spallation Source ESS AB; Lunds universitet/Synkrotronljusfysik

    Author : Gustav Gird Fahlström; [2022]
    Keywords : ESS; European Spallation Source; Proton beam; waist; BPM; Method; transverse; beam dynamics; beam physics; Lattice Error; Matrix formalism; Python; trajectory simulation; physics; Physics and Astronomy;

    Abstract : In this work, we examine a novel method for the determination of proton beam waist locations using beam position monitors. Based on the lattice of the final transport line section of the European Spallation Source linac, a simplified version of the beam line composed of quadrupole magnets and correctors is constructed in Python using a matrix formalism. READ MORE

  5. 24. Hydrogen Absorption in Metal Hydrides : Transmission of light in relation to hydrogen concentration and site occupancy of ultrathin vanadium films

    University essay from Uppsala universitet/Tillämpad kärnfysik

    Author : David Sörme; [2022]
    Keywords : metal hydrides; iron-vanadium superlattice; hydrogen; hydrogen site occupancy; hydrogen concentrationm; hydrogen storage;

    Abstract : In this study the effect of hydrogenation on the optical properties in the wavelength range 400-1023 nm of an ultrathin iron-vanadium superlattice is investigated. Specifically, mea- surements of transmission are performed under different states of hydrogenation, along with measurements of absolute hydrogen concentration and hydrogen site occupancy. READ MORE

  6. 25. Ab inito calculation of the formation energy of the sigma phases at 1000 Kelvin : With a five sublattice model for the ternary Iron-Chromium-Nickel system

    University essay from KTH/Materialvetenskap

    Author : Fabian Mathias Veid; [2022]
    Keywords : ;

    Abstract : This project investigates the σ-phase formation energy at 1000 Kelvin using Exact Muffin TIn Orbital (EMTO) method and considers the disordered local moment approach to handle the paramagnetism in a self-consistent manner. The sigma phase is detrimental and causes embrittlement when it occurs primarily in stainless steel and superalloys with Iron (Fe) and Chromium (Cr), which is why it is necessary to understand it better and therefore avoid it. READ MORE